Influence of morphological parameters on the development of gingival recession in class III malocclusion

Analysis of alveolar ridge width in an area of central lower incisor using cone-beam computed tomography in vivo

BACKGROUND

Planning a comprehensive dental treatment should include assessment and classification of the condition of the alveolar ridge. Existing classifications are insufficient. This study aimed to investigate the frequency of bone deficiencies in the anterior mandible and to develop an extension of one of the alveolar bone dehiscence classification.

METHODS

Cone-beam computed tomography scans of 100 adults with the mean age of 36.75 ± 11.77 years were analyzed. Measurements were taken from the 31. tooth.

RESULTS

The presence of any bone defect was found in 91 (91%) of cases. Fenestrations were detected in 9% of study images, and dehiscence were detected in 90% of study images. A thin alveolar plate of below 0.2 mm independent from the side was found in 37 (37%) of cases. The mean height of buccal fenestration was 3.10 ± 1.09 mm, and the mean height of lingual fenestration was 2.73 ± 0.91 mm. The mean height of buccal dehiscence was 4.39 ± 1.82 mm, and the mean height of lingual dehiscence was 4.27 ± 2.49 mm.

CONCLUSIONS

An attempt to restore the correct morphology of the alveolar process after improper treatment constitutes a therapeutic challenge. The frequent occurrence of bone deficiency prompts establishing safe treatment planning strategies, including careful assessment of the alveolar process supported by the comprehensive classification of bone defects.

Three-Dimensional Bone Block Planning for Mandibular Sagittal Bone Defect Reconstruction

Bone defects seen in severe sagittal discrepancies between the maxilla and mandible do not solely qualify for orthodontic treatment. An interdisciplinary approach with the aid of a surgical, orthodontic, and periodontal team should be implemented in the treatment of such cases. Despite the use of standard treatment methods, the therapy is always planned and carried out individually for each patient. The surgical treatment of bone defects in the area of the jawbones is associated with a number of potential complications. Regenerative medicine, which has already been practiced in reconstructive surgery, is now gradually receiving more attention in the treatment of orthognathic defects. We developed a method for the reconstruction of the alveolar bone in the sagittal dimension using 3D allogenic graft blocks, as a preparing feature in the orthodontic treatment of borderline cases or as a treatment option for complications arising during general orthodontic treatment.

Volumetric characteristics of prognathic mandible revealed by skeletal unit analysis

The purpose of this study was to evaluate the skeletal units of a normal mandible (class I) and a prognathic mandible (class III), to compare the groups, and to investigate the key functional unit responsible for mandibular prognathism. Hemi-mandibles of 101 cases were evaluated by cone-beam computed tomography. Of these, 50 cases had Class I and 51 had Class III mandibles. The length, volume, and volume/length ratio of each skeletal unit were measured. The ratios of the condyle, body unit, and sum of the hemi-mandible between Class I and Class III showed statistically significant results (P<0.05). However, the ratios of angle, coronoid, and symphysis units did not show any statistical significance on comparison. Dependent on gender, in males the ratio of the condyle of the hemi-mandible showed statistically significant results (P<0.05). Meanwhile in females the ratio of the body and sum of the hemi-mandible showed statistically significant results (P<0.05). Accordingly, the mandibular body and condylar units are thinner in mandibular prognathism. On the basis of the functional matrix theory to determine the aetiology of mandibular prognathism, the key skeletal units are the body and condylar units.